fileAttribCompatible: handle string for Matlab < R2018a

Author: scivision

+stdlib/private/fileAttribCompatible.m

@@ -2,6 +2,15 @@
 
 function [s, r, id] = fileAttribCompatible(file)
 
+% need stdlib.strempty for Matlab < R2020b
+if stdlib.strempty(file)
+  r = struct.empty;
+  s = 0;
+  id = 'MATLAB:FILEATTRIB:CannotFindFile';
+  return
+end
+
+
 try
   [s, r, id] = fileattrib(file);
 catch e

+stdlib/private/file_attributes.m

@@ -1,19 +1,12 @@
 function a = file_attributes(p)
 
-a = struct.empty;
-
-% need stdlib.strempty for Matlab < R2020b
-if stdlib.strempty(p)
-  return
-end
-
-[status, s] = fileattrib(p);
+[status, a] = fileAttribCompatible(p);
 
 if status ~= 1
+  a = struct.empty;
   return
 end
 
-a = s;
 for n = ["GroupRead", "GroupWrite", "GroupExecute", "OtherRead", "OtherWrite", "OtherExecute"]
 
   if ~isfield(a, n) || isnan(a.(n))